Digital signal processing of digital images is well known in the art. Digital filters have been in existence for many years both in the literature (e.g. Rabiner L.R. and Schafer, "Digital Processing of Speech Signals", Prentice Hall, 1978) and various patents (e.g. U.S. Pat. Nos. 4,063,060; 4,034,197 and 5,170,369). Furthermore, many filter architectures have been developed to improve filter response and simplify filter development. The determination of filter co-efficients required to obtain a desired frequency response has been addressed in many text books and is a well known topic in university digital signal processing courses. The complexity of digital filters and the precision of the operations required to perform image filtering vary widely depending upon the filter operation that is selected.
Recent advances have been made in the digital signal processing of images to effect image resizing. One example of such an innovation is disclosed in U.S. patent application No. 07/766,128. In particular, an integrated circuit implementation of the image resizing engine disclosed in U.S. patent application No. 07/766,128, has recently been fabricated. These resizing circuits eliminate aliasing distortion in reduction mode and imaging distortion in magnification mode.